Certification - NSF-ANSI.031.NSF-ANSI 49.pdf

NSF International Standard / American National Standard

NSF/ANSI 49 - 2010

Biosafety Cabinetry: Design, Construction, Performance, and Field Certification

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NSF/ANSI 49 – 2010

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NSF International Standard/ American National Standard for Biosafety Cabinetry –

Biosafety Cabinetry: Design, Construction, Performance, and

Field Certification

Standard Developer

NSF International

Designated as an ANSI Standard September 16, 2010 American National Standards Institute ii

Prepared by The NSF Joint Committee on Biosafety Cabinetry

Recommended for Adoption by The NSF Council of Public Health Consultants

Adopted by The NSF Board of Trustees June 1976

Revised May 1983 Revised June 1987 Revised May 1992 Revised March 2002 Addendum November 2002 Revised February 2004 Revised September 2004 Addendum October 2004 Addendum March 2005 Revised July 2007 Revised October 2008 Revised June 2009 Revised September 2010

Published by

PO Box 130140, Ann Arbor, Michigan 48113-0140, USA

For ordering copies or for making inquiries with regard to this Standard, please reference the designation

“NSF/ANSI 49 – 2010.”

Copyright 2010 NSF International Previous edition © 2009, 2008, 2007, 2004, 2002, 1992, 1987, 1983, 1976

Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from NSF International.

Printed in the United States of America.

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Disclaimers1

NSF International (NSF), in performing its functions in accordance with its objectives, does not assume or undertake to discharge any responsibility of the manufacturer or any other party. The opinions and findings of NSF represent its professional judgment. NSF shall not be responsible to anyone for the use of or reliance upon this Standard by anyone. NSF shall not incur any obligation or liability for damages, including consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this Standard.

NSF Standards provide basic criteria to promote sanitation and protection of the public health. Provisions for mechanical and electrical safety have not been included in this Standard because governmental agencies or other national standards-setting organizations provide safety requirements.

Participation in NSF’s Standards development activities by regulatory agency representatives (federal, local, state) shall not constitute their agency's endorsement of NSF or any of its Standards.

Preference is given to the use of performance criteria measurable by examination or testing in NSF Standards development when such performance criteria may reasonably be used in lieu of design, materials, or construction criteria.

The illustrations, if provided, are intended to assist in understanding their adjacent standard requirements.

However, the illustrations may not include all requirements for a specific product or unit, nor do they show the only method of fabricating such arrangements. Such partial drawings shall not be used to justify improper or incomplete design and construction.

Unless otherwise referenced, the annexes are not considered an integral part of NSF Standards. The annexes are provided as general guidelines to the manufacturer, regulatory agency, user, or certifying organization.

1 The information contained in this Disclaimer is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI’s requirements for an ANS. Therefore, this Disclaimer may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the Standard.

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Contents

1 General

1.1 Scope

1.2 Minimum requirements

1.3 Variations in design and construction

2 Normative references

3 Definitions

4 Materials

4.1 General

4.2 Interior work surfaces

4.3 Exposed interior surfaces

4.4 Other interior and exterior surfaces

4.5 Materials and finishes

5 Design and construction

5.1 General

5.2 Cleanability

5.3 Decontamination

5.4 Duct and Plenum design

5.5 Internal corners and angles

5.6 External corners and angles

5.7 Joints and seams

5.8 Fastening methods

5.9 Welds

5.10 Solder

5.11 Removable panels

5.12 Stability

5.13 Provision for mounting

5.14 Legs and feet

5.15 Reinforcing and framing

5.16 Fixed panels

5.17 Doors and covers

5.18 Louvers and openings

5.19 Tracks and guides

5.20 Filters

5.21 Gaskets and sealants

5.22 Stopcocks and service outlets

5.23 Alarms

5.24 Electrical components

5.25 Lighting

5.26 Gauges

5.27 Drain spillage trough

5.28 Diffuser placement

5.29 Work area components placement

5.30 Height and width

5.31 Data plate(s)

6 Performance

6.1 General

6.2 Pressure decay / soap bubble / tracer gas leak

6.3 HEPA/ULPA filter leak

6.4 Noise level

6.5 Lighting intensity

6.6 Vibration

6.7 Personnel, product, and cross-contamination protection

6.8 Stability

6.9 Downflow velocity

6.10 Inflow velocity

6.11 Airflow smoke patterns

6.12 Drain spillage trough leakage

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6.13 Motor/blower performance

6.14 Electrical safety

6.15 Performance data

6.16 Record maintenance

Annex A ................................................................................................................................................. A1 A.1 Pressure decay / soap bubble ....................................................................................................... A1 A.2 HEPA/ULPA filter leak test ............................................................................................................. A2 A.3 Noise level test ............................................................................................................................... A4 A.4 Lighting intensity test ...................................................................................................................... A5 A.5 Vibration test .................................................................................................................................. A5 A.6 Personnel, product, and cross-contamination protection (biological) tests ................................... A6 A.7 Stability tests ................................................................................................................................ A11 A.8 Downflow velocity ......................................................................................................................... A13 A.9 Inflow velocity (face velocity) test ................................................................................................. A15 A.10 Airflow smoke patterns test ................................................................................................... A18 A.11 Drain spillage trough leakage test ......................................................................................... A19 A.12 Motor/blower performance ..................................................................................................... A19

Annex B ................................................................................................................................................. B1 B.1 Method to verify fitness for use of potential direct inflow measurement devices ........................... B1

Annex C ................................................................................................................................................. C1 C.1 Selection ........................................................................................................................................ C1 C.2 Calibration ...................................................................................................................................... C1

Annex D ................................................................................................................................................. D1 D.1 Chemical resistance ....................................................................................................................... D1 D.2 Abrasion resistance ........................................................................................................................ D1

Annex E ................................................................................................................................................. E1 E.1 Biosafety Consultation Prior to BSC Purchase .............................................................................. E1 E.2 Risk Assessment Procedure .......................................................................................................... E1 E.3 Biosafety Cabinet Selection ........................................................................................................... E3 E.4 Prior to the Purchase ..................................................................................................................... E9 E.5 Inspection ..................................................................................................................................... E11 E.6 Moving a Permanently Installed Biosafety Cabinet ..................................................................... E11 E.7 Lifespan of BSCs ......................................................................................................................... E11 E.8 Decommissioning process ........................................................................................................... E12

Annex F ................................................................................................................................................. F1 F.1 Field certification preconditions and intervals ............................................................................... F1 F.2 Downflow velocity .......................................................................................................................... F2 F.3 Inflow velocity (face velocity) test .................................................................................................. F3 F.4 Airflow smoke patterns test ........................................................................................................... F8 F.5 HEPA/ULPA filter leak test ............................................................................................................ F9 F.6 Pressure decay / soap bubble .................................................................................................... F11 F.7 Site installation assessment tests ............................................................................................... F12 F.8 Electrical leakage and ground circuit resistance and polarity tests ............................................ F13 F.9 Lighting intensity test ................................................................................................................... F14 F.10 Vibration test .......................................................................................................................... F14 F.11 Noise level tests .................................................................................................................... F15 F.12 Record of field certification .................................................................................................... F16

Annex G ................................................................................................................................................ G1 G.1 Recommended microbiological decontamination procedure ........................................................ G1 G.2 Recommended HEPA/ULPA Filter Disposal Procedures ............................................................. G8

Annex H ................................................................................................................................................. H1 H.1 Sheet metal and finishes ................................................................................................................ H1 H.2 Glass .............................................................................................................................................. H1 H.3 HEPA/ULPA filter gasket materials ................................................................................................ H1 H.4 HEPA/ULPA filter case – Type IC .................................................................................................. H2 H.5 Specifications ................................................................................................................................. H2 vii

H.6 Sealants ......................................................................................................................................... H2 H.7 Fans ............................................................................................................................................... H2 H.8 Components and wiring ................................................................................................................. H2

Annex I .................................................................................................................................................. I1 I.1 Miscellaneous publications ............................................................................................................. I1 I.2 Federal specifications ..................................................................................................................... I2 I.3 Federal standards ........................................................................................................................... I3 I.4 Military specifications ...................................................................................................................... I3

Annex J ................................................................................................................................................. J1 J.1 Helium leak test .............................................................................................................................. J1 J.2 Sulfur hexafluoride (SF6) leak test ................................................................................................. J2

Annex K ................................................................................................................................................. K1 K.1 Introduction .................................................................................................................................... K1 K.2 Protocol .......................................................................................................................................... K1 viii ix

Foreword2

The purpose of this Standard is to establish minimum requirements for materials, design, construction, and performance of Biosafety Cabinetry that are designed to protect personnel, product, and the environment. This Standard details requirements for performance testing as well as field certification testing.

This edition of the Standard (NSF/ANSI 49-2010) includes the following revisions:

Issue 23 - Hard Ducting Cabinets Revision language was added to disallow certification of direct connected Type A biosafety cabinets. In addition, reference to HEPA was updated to include ULPA and definitions were revised.

Issue 24 - Alarms Revision language was added requiring alarms on canopy connected type A1 or A2 cabinets.

Issue 37/38 - Illustrations The purpose of this revision was to update Illustrations and references in the standard.

Issue 41 - IEC 61010 The Standard was revised to be more inclusive of markets outside North America by modifying Section 6

- Performance of the Standard.

This Standard was developed by the NSF Joint Committee on Biosafety Cabinetry using the consensus process described by the American National Standards Institute.

Suggestions for improvement of this Standard are welcome. Comments should be sent to Chair, Joint Committee on Biosafety Cabinetry, c/o NSF International, Standards Department, PO Box 130140, Ann Arbor, Michigan 48113-0140, USA.

2 The information contained in this Foreword is not part of this American National Standard (ANS) and has not been processed in accordance with ANSI’s requirements for an ANS. As such, this Foreword may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the Standard.

© 2010 NSF NSF/ANSI 49 – 2010

NSF/ANSI International Standard for Biosafety Cabinetry —

Biosafety Cabinetry: Design, Construction, Performance, and Field Certification

1 General

1.1 Scope

This Standard applies to Class II (laminar flow) biosafety cabinetry designed to minimize hazards inherent in work with agents assigned to biosafety levels 1, 2, 3, or 4. It also defines the tests that shall be passed by such cabinetry to meet this Standard. This Standard includes basic requirements for the design, construction, and performance of biosafety cabinets that are intended to provide personnel, product, and environmental protection; reliable operation; durability and structural stability; cleanability; limitations on noise level; illumination; vibration; and motor/blower performance.

1.2 Minimum requirements

Cabinets qualifying under this Standard shall have passed all of the designated tests. Units with component parts covered under existing NSF standards or criteria shall conform to those applicable requirements.

1.3 Variations in design and construction

Cabinetry varying in design, construction, or installation of accessory equipment may qualify under this Standard, if appropriate tests and investigations indicate that the equipment is durable and reliable, can be cleaned and decontaminated, and performs in conformance to this Standard. Such equipment shall meet the requirements for materials and finishes in this Standard.

Major modifications require appropriate tests for conformance. Major modifications include, but are not limited to, changes in the following: location or capacity or quantity or all three of blower/motor(s); size or design or both of air plenums; position of High Efficiency Particulate Air (HEPA) filters; position or redesign of work surface; work area intake and exhaust air grilles; window placement or design; access opening size; location and size of exhaust port; and built-in accessory equipment (centrifuges, ultraviolet lighting, supports for intravenous drug container, arm rests, etc.). Relocation of utility service equipment (electrical outlets, petcocks, etc.) is not considered a major modification if other provisions of this Standard are not compromised.

2 Normative references

The following documents contain requirements that, by reference in this text, constitute requirements of this Standard. At the time of publication, the indicated editions were valid. All documents are subject to revision, and parties are encouraged to investigate the possibility of applying the most recent editions of the documents indicated below.

ACGIH, Industrial Ventilation, A Manual of Recommended Practice3

3 American Conference of Governmental Industrial Hygienists, 1330 Kemper Meadow Dr., Cincinnati, OH 45240 <www.acgih.org>

© NSF 2010 NSF/ANSI 49 – 2010

ANSI 226.1 – Test No. 17 4

ANSI/NFPA 70, 1999, National Electrical Code5

APHA, Compendium of Methods for Microbiological Examination of Foods, 1976 (Spore staining techniques)6

APHA, Standard Methods for the Examination of Water and Wastewater, Seventeenth Edition (Standard dilution plate methods)6

ASHRAE, Standard 111-2008 Practices for Measurement, Testing, Adjusting and Balancing of Building Heating, Ventilation, Air-Conditioning and Refrigeration Systems7

IES, Illuminating Engineering Society Lighting Handbook8

IEST-RP-CC-001, Recommended Practice for HEPA Filters8

IEST-RP-CC007, Testing ULPA Filters8

IEST-RP-CC-013, Institute of Environmental Sciences Recommended Practice, Tentative, August, 19869

IEST-RP-CC021,Testing HEPA and ULPA Filter Media8

MIL-F-51079B, Filters, Particulate, High Efficiency, Fire Resistant, Biological Use10

NIOSH, Department of Health and Human Services (DHHS) reports in "Hazard Review of Bis(chloromethyl)ether (BCME)11

OSHA Regulations, Code of Federal Regulations, Title 29, December 6, 1991, OSHA Bloodborne Pathogen Standard: 1910.10012

UL Standard 9413

4 American National Standards Institute, 25 West 43rd Street, Fourth Floor, New York, NY 10036 <www.ansi.org>

5 National Fire Protection Association, 1 Batterymarch Park, Quincy, MA 02269 <www.nfpa.org>

6 American Public Health Association, 800 I Street, NW, Washington, DC 20001 <www.apha.org>

7 American Society of Heating, Refrigerating, and Air-Conditioning Engineers, 1791 Tullie Circle, N. E. Atlanta, GA 30329 <www.ashrae.org>

8 Illuminating Engineering Society, 345 E. 47th St., New York, NY 10017 <www.iesna.org>

9 Institute of Environmental Sciences and Technology, 5005 Newport Drive, Suite 506, Rolling Meadows, IL 60008- 1699 <www.iest.org>

10 U. S. Department of Defense, Navy Publishing and Printing Service Office, 700 Robins Ave., Philadelphia, PA 19111-5094 <www.defenselink.mil/pubs/>

11 NIOSH, Department of Health and Human Services (DHHS), Publications Office, 4676 Columbia Pkwy., Cincinnati, OH 45226 <www.cdc.gov/niosh/>

12 Superintendent of Documents, U. S. Government Printing Office, Washington, DC 20402 <www.gpo.gov>

13 Underwriters Laboratories, 333 Pfingsten Rd., Northbrook, IL 60062-2096 <www.ul.com>

UL Standard 61010A-113

UL Standard 61010-113

3 Definitions

3.1 accessible: Fabricated to be exposed for cleaning and visual inspection using simple tools (screwdriver, pliers, open-end wrench, etc. [Also see 3.18, “readily accessible.”]).

3.2 biohazard (a contraction of the words biological and hazard): Infectious agent(s), or part thereof, presenting a real or potential risk to the well-being of man, animals, and/or plants, directly through infection or indirectly through disruption of the environment.

3.3 biosafety levels:14 The combination of laboratory practices and techniques, safety equipment, and laboratory facilities appropriate for the operations performed and the hazard posed by the infectious agents and the laboratory function or activity. These biosafety levels are described in Biosafety in Microbiological and Biomedical Laboratories.15

3.3.1 biosafety level 1: Practices, safety equipment, and facility design and construction are appropriate for undergraduate and secondary educational training and teaching laboratories and for other laboratories in which work is done with defined and characterized strains of viable microorganisms not known to consistently cause disease in healthy adult humans. Bacillus subtilis, Naegleria gruberi, infectious canine hepatitis virus, and exempt organisms under the NIH Guidelines for Research Involving Recombinant DNA Molecules16 are representative of those microorganisms meeting these criteria. Many agents not ordinarily associated with disease processes in humans are, however, opportunistic pathogens and may cause infection in the young, the aged, and immunodeficient or immunosuppressed individuals. Vaccine strains that have undergone multiple in vivo passages should not be considered avirulent simply because they are vaccine strains.

Biosafety Level 1 represents a basic level of containment that relies on standard microbiological practices with no special primary or secondary barriers recommended, other than a sink for hand washing.

3.3.2 biosafety level 2: Practices, equipment, and facilities are applicable to clinical, diagnostic, teaching, and other facilities in which work is done with the broad spectrum of indigenous moderate-risk agents present in the community and associated with human disease of varying severity. With good microbiological techniques, these agents can be used safely in activities conducted on the open bench, if the potential for producing aerosols is low. Hepatitis B virus, human immunodeficiency virus, the salmonellae, and Toxoplasma spp. are representative of microorganisms assigned to this containment level. Biosafety Level 2 is appropriate when work is done with any human-derived blood, body fluids, tissues, or primary human cell lines where the presence of an infectious agent may be unknown.

(Laboratory personnel working with human-derived materials should refer to the OSHA Bloodborne Pathogen Standard for specific required precautions.)

Primary hazards to personnel working with these agents may include accidental percutaneous or mucous membrane exposures or ingestion of infectious materials. Extreme caution should be taken with contaminated needles and sharp instruments. Even though organisms routinely manipulated at Biosafety

14 Previously referred to as risk levels (low, moderate, and high)

15 U.S. Department of Health and Human Services, DHHS Publication CDC 93-8395, U.S. Government Printing Office, Washington, DC 20402 <www.gpo.gov>

16 Department of Health and Human Services, National Institute of Health, 6705 Rockledge Drive, Suite 750, MSC 7985, Bethesda, MD 20892-7985 <www.nih.gov>

Level 2 are not known to be transmissible by the aerosol route, procedures with aerosol or high splash potential, which may increase the risk of such personnel exposure, must be conducted in primary containment equipment or in devices such as biosafety cabinets (BSCs) or safety centrifuge cups. Other primary barriers should be used as appropriate, such as splash shields, face protection, gowns, and gloves.

Secondary barriers such as hand washing sinks and waste decontamination facilities must be available to reduce potential environmental contamination.

3.3.3 biosafety level 3: Practices, safety equipment, and facility design and construction are applicable to clinical, diagnostic, teaching, research, or production facilities in which work is done with indigenous or exotic agents with a potential for respiratory transmission and that may cause serious and potentially lethal infection. Mycobacterium tuberculosis, St. Louis encephalitis virus, and Coxiella burnetii are representative of the microorganisms assigned to this level. Primary hazards to personnel working with these agents relate to autoinoculation, ingestion, and exposure to infectious aerosols.

At biosafety level 3, more emphasis is placed on primary and secondary barriers to protect personnel in contiguous areas, the community, and the environment from exposure to potentially infectious aerosols.

For example, all laboratory manipulations should be performed in a BSC or other enclosed equipment, such as a gas-tight aerosol generation chamber. Secondary barriers for this level include controlled access to the laboratory and ventilation requirements that minimize the release of infectious aerosols from the laboratory.

3.3.4 biosafety level 4: Practices, safety equipment, and facility design and construction are applicable for work with dangerous and exotic agents that have a high individual risk of life-threatening disease, which may be transmitted via the aerosol route and for which there is no available vaccine or therapy. Agents with a close or identical antigenic relationship to biosafety level 4 agents also should be handled at this level. When sufficient data are obtained, work with these agents may continue at this level or at a lower level. Viruses such as Marburg or Congo-Crimean hemorrhagic fever are manipulated at biosafety level 4.

The primary hazards to personnel working with Biosafety Level 4 agents are respiratory exposure to infectious aerosols, mucous membrane or broken skin exposure to infectious droplets, and autoinoculation. All manipulations of potentially infectious diagnostic materials, isolates, and naturally or experimentally infected animals pose a high risk of exposure and infection to laboratory personnel, the community, and the environment.

The laboratory worker's complete isolation from aerosolized infectious materials is accomplished primarily by working in a Class III BSC or in a full-body, air-supplied, positive-pressure personnel suit. The Biosafety Level 4 facility itself is generally a separate building or completely isolated zone with complex, specialized ventilation requirements and waste management systems to prevent release of viable agents to the environment.

3.4 cabinet classification: Although this Standard covers only Class II biosafety cabinetry, Class I and Class III cabinets are currently defined and known to be commercially available. Biosafety cabinets can be used for work with biological agents assigned to biosafety levels 1 through 4, depending on the facility design as described in Biosafety in Microbiological and Biomedical Laboratories. Special note should be taken that BSL 4 agents should only be used in Maximum Containment Laboratories and that Class I and Class II biosafety cabinets are only acceptable in Maximum Containment Laboratories with positive pressure containment suits.

3.4.1 Class I: A ventilated cabinet for personnel and environmental protection, having an un-recirculated inward airflow away from the operator that exhausts all air to the atmosphere after filtration through a HEPA/ULPA filter. Class I cabinets are suitable for work where no product protection is required.

NOTE – Although the traditional Class I BSC is exhausted to the atmosphere without recirculation into the lab, it is recognized that some of the benefits of the Class I BSC can be obtained even when the unit’s HEPA/ULPA filtered exhaust is vented back into the laboratory.

3.4.2 Class II: A ventilated cabinet for personnel, product, and environmental protection having an open front with inward airflow for personnel protection, downward HEPA/ULPA filtered laminar airflow for product protection, and HEPA/ULPA filtered exhausted air for environmental protection.

NOTE – When toxic chemicals or radionuclides are used as adjuncts to biological studies or pharmaceutical work, Class II cabinets designed and constructed for this purpose should be used.

3.4.2.1 Class II Type A1 cabinets (formerly designated Type A): cabinets that

– maintain minimum average inflow velocity of 75 ft/min (0.38 m/s) through the work access opening;

– have HEPA/ULPA filtered downflow air that is a portion of the mixed downflow and inflow air from a common plenum (i.e., a plenum from which a portion of the air is exhausted from the cabinet and the remainder supplied to the work area);

– may exhaust HEPA/ULPA filtered air back into the laboratory or to the environment through an external exhaust system connected to the cabinet with a canopy connection; and

– have all biologically contaminated ducts and plenums under negative pressure or surrounded by negative pressure ducts and plenums.

Type A1 cabinets are not suitable for work with volatile chemicals and tracer amounts of volatile radionuclides.

3.4.2.2 Class II, Type A2 cabinets (when exhausted to the environment were formerly designated Type B3): cabinets that

– maintain a minimum average inflow velocity of 100 ft/min (0.51 m/s) through the work access

– have HEPA/ULPA filtered downflow air that is a portion of the mixed downflow and inflow air from a common exhaust plenum;

– may exhaust HEPA/ULPA filtered air back into the laboratory or to the environment through an external exhaust system connected to the cabinet with a canopy connection; and

Type A2 cabinets used for work with minute quantities of volatile chemicals and tracer amounts of volatile radionuclides required as an adjunct to microbiological studies must be exhausted through properly functioning exhaust canopies.

3.4.2.3 Class II Type B1 cabinets: cabinets that

– have HEPA/ULPA filtered downflow air composed largely of uncontaminated recirculated inflow air;

– exhaust most of the contaminated downflow air to an external exhaust system through a dedicated duct connected to cabinet with a direct connection and exhausted to the atmosphere after passing through a HEPA/ULPA filter; and

Type B1 cabinets may be used for work with volatile chemicals and tracer amounts of volatile radionuclides required as an adjunct to microbiological studies if work is done in the direct exhausted portion of the cabinet, or if the chemicals or radionuclides will not interfere with the work when recirculated in the downflow air.

3.4.2.4 Class II, Type B2 cabinets: cabinets that

– have HEPA/ULPA filtered downflow air drawn from the laboratory or the outside air (i.e., downflow air is not recirculated from the cabinet exhaust air);

– have HEPA/ULPA filtered downflow air that is a portion of the mixed downflow and inflow air from a common exhaust plenum;

– may exhaust HEPA/ULPA filtered air back into the laboratory or to the environment through an external exhaust system connected to the cabinet with a canopy connection; and

– have HEPA/ULPA filtered downflow air drawn from the laboratory or the outside air (i.e., downflow air is not recirculated from the cabinet exhaust air).

Type B2 cabinets may be used for work with volatile chemicals and radionuclides required as adjuncts to microbiological studies.

3.4.3 Class III: A totally enclosed, ventilated cabinet of leak-tight construction. Operations in the cabinet are conducted through attached rubber gloves. The cabinet is maintained under negative air pressure of at least 0.50 in w.g. (120 Pa). Downflow air is drawn into the cabinet through HEPA/ULPA filters. The exhaust air is treated by double HEPA/ULPA filtration or by HEPA/ULPA filtration and incineration.17

3.5 calibration: Comparison of the measurement of a standard or instrument of unknown accuracy with another standard or instrument of known accuracy to detect, correlate, report, or eliminate by adjustment any variation in the accuracy of the unknown standard or instrument.

3.6 canopy connection: A BSC exhaust connection where there are one or more openings or gaps in the connection between the BSC and the external exhaust system.

3.7 certification, cabinet design: Cabinet design certification is formal validation by a qualified design testing organization that a designated cabinet model meets all the requirements of annex A of this standard.

3.8 certification, cabinet field: Cabinet field certification is formal verification by a qualified field-testing certifier that an installed cabinet meets all the requirements of annex F of this standard.

17 National Institute of Health, "Supplement to Recombinant DNA Guidelines," Laboratory Safety Monograph, January 1979 www.nih.gov

3.9 chemical resistance: Capability of materials to maintain their original surface characteristics under prolonged contact with cleaning compounds, decontaminating agents, and normal conditions of the use environment.

3.10 closed: Fabricated with no openings exceeding 0.031 in (0.079 cm).

3.11 concurrent balance value: This value is determined using the duct traverse measurement method as specified in ASHRAE Standard 111-2008, a minimum of 7.5 duct diameters downstream of a direct connected BSC. Prior to determining the concurrent balance value, it shall be confirmed that the cabinet is operating at its nominal setpoints for inflow and downflow velocity ± 3 fpm. The primary DIM method shall be used for setting the inflow velocity. The accuracy of the DIM shall be better than or equal to ± 3% and ± 7 cfm. The static pressure is also measured approximately two duct diameters from the cabinet exhaust connection. Appropriate filter load and tolerance values shall be added to the base static pressure value to accommodate filter loading: 0.3 in w.g. shall be added for Type B1 cabinets and

0.7 in w.g. shall be added for Type B2 cabinets. The resulting values may be used for design and balance exhaust/supply HVAC requirements.

3.12 decontamination: Inactivation or destruction of infectious agents or neutralization of toxic agents.

3.13 direct connection: A BSC exhaust connection where the connection between the BSC and the external exhaust system is air tight with no designed gaps or openings.

3.14 direct inflow measuring device (DIM): A volumetric airflow measuring device consisting of a capture hood with a sensing component that provides a readout as a single value for volumetric flow rate and meets the requirements of annex B.

3.15 downflow velocity – 4 inches: The flow of air in the cabinet coming from the downflow HEPA/ULPA filters down into the work area at a point 4 in (10 cm) above the lower level of the window sash.

3.16 high efficiency air filters (for use in class II biosafety cabinets):

3.16.1 high efficiency particulate air (HEPA) filter: A throwaway, extended/pleated medium, dry-type filter with the following:

– rigid casing enclosing the full depth of the pleats;

– minimum particulate removal of 99.99% for thermally generated monodisperse dioctylphthalate (DOP) smoke particles or equivalent with a diameter of 0.3 µm (Type C);

– minimum particulate removal of 99.99% and determination as the lower efficiency when tested for particle size ranges of 0.1 to 0.2 µm or 0.2 to 0.3 µm in accordance with IEST-RP-CC007 (Type J);

– minimum particulate removal of 99.995% and determination as the lower efficiency when tested for particle size ranges of 0.1 to 0.2 µm or 0.2 to 0.3 µm in accordance with IEST-RP-CC007 (Type K);

– maximum pressure drop of 1.0 in w.g. (250 Pa) when clean and operated at rated airflow capacity; and

– no area showing a penetration exceeding 0.01% when scan tested with a polydisperse aerosol having a light scattering median size of 0.7 µm and a geometric standard deviation of 2.4.

These filters conform to all the performance and construction requirements of a Type C, a Type J, or a Type K filter respectively, contained in IEST-RP-CC001.4. Filter media shall be tested in accordance with the methods of IEST-RP-CC021 with performance levels to meet the minimum efficiency requirements as specified above and the pressure drop requirements as required by the specific application.

3.16.2 ultra-low-penetrating air (ULPA) filter: A throw away, extended/pleated medium, dry-type filter with the following:

– rigid frame enclosing the full depth of the pleats;

– minimum particle removal of 99.999% and determination as the lower efficiency when tested for particle size ranges of 0.1 to 0.2 µm or 0.2 to 0.3 µm when tested in accordance with IEST-RP-

CC007;

– maximum pressure drop of 1.0 in w.g. (250 Pa) when clean and operated at rated airflow capacity. ULPA filters may have higher airflow resistance than HEPA/ULPA filters for the same rated airflow; therefore, care shall be taken to ensure that the pressure drop is compatible with the cabinet motor/ blower capability; and

– no area showing a penetration exceeding 0.01% when scan tested with a polydisperse aerosol having a light scattering median size of 0.7 µm and a geometric standard deviation of 2.4.

This filter conforms to all requirements of a Type F filter contained in IEST-RP-CC001.4, HEPA and ULPA filters.

3.17 laminar airflow: Unidirectional airflow through the work area often referred to as turbulence-free airflow; steady, unidirectional micro-turbulence flow; or mass airflow.

3.18 leak tight: Free of leaks at 2 in w.g. (500 Pa) of air pressure as described in annex A.

3.19 nominal set point velocities: The cabinet downflow and inflow velocities that the manufacturer designates as the settings at which the cabinet is intended to operate and the settings at which it passed the tests listed in 6.7 and annex A, section A.7.

3.20 polydisperse aerosol: Aerosol with a light scattering median size of 0.7 m and a geometric standard deviation of 2.4.

3.21 readily accessible: Fabricated to be exposed for cleaning and visual inspection without using tools.

3.22 readily removable: Capable of being taken away from the main unit without using tools.

3.23 removable: Capable of being taken away from the main unit using simple tools (screwdriver, pliers, open-end wrench, etc. [also see definition of “readily removable”]).

3.24 sealed: Fabricated with no openings that will permit entry or leakage of air (leak-tight).

3.25 smooth: A surface free of pits and inclusions, with cleanability equal to or exceeding the following.

3.25.1 interior work surfaces and exposed interior surfaces: Number 3 (100 grit) finish on stainless steel.

3.25.2 other interior surfaces and exterior surfaces: Commercial grade cold-rolled, hot-rolled, or combination cold/hot-rolled steel free of visible scale.

3.26 surfaces: (see figure 1)

3.26.1 interior work surfaces: Surfaces used when performing a task, operation, or activity.

3.26.2 exposed interior surfaces: Exposed interior surfaces, other than work surfaces, that are subject to splash, spillage, or airborne contamination during normal use.

3.26.3 other interior surfaces: Interior surfaces not exposed to splash or spillage but exposed to vapor or volatile toxic substances or both.

3.26.4 exterior surfaces: All exposed surfaces not defined as interior.

3.27 toxic: Having an adverse physiological effect on biological systems.

3.28 visible medium: A visible aerosol that is sufficiently neutrally buoyant in air to see air disturbances without influencing them. Examples include chemical ventilation tubes and thermally generated aerosol. The delivery velocity of the visual medium should be slow enough to assure that there is no interference to the air flow under test.

3.29 w.g. (water gauge): Another common name for the inch of water column. The word "gauge" after a pressure reading indicates that the pressure stated is actually the difference between the absolute or total pressure and the air pressure at the time of the reading.

3.30 work area: The horizontal plane inside the cabinet extending from sidewall to sidewall and from back wall to the inside of the window or sash at a point approximately 2 in (5 cm) above the lower level of the window sash.

3.31 work tray: The solid floor of the work area identified by the manufacturer as the location for the user’s activity. This is differentiated from work area.

4 Materials

4.1 General

Materials shall withstand normal wear, corrosive action of gases or liquids, cleaning compounds, and decontaminating agents and procedures. Materials shall be structurally sound, dimensionally stable, fire and moisture resistant, and compatible with other materials used in the laboratory.18

4.2 Interior work surfaces

Interior work surfaces shall be smooth, 300-series stainless steel.

4.3 Exposed interior surfaces

Exposed interior surfaces shall be smooth and abrasion- and corrosion-resistant or shall be rendered corrosion-resistant with nontoxic material that resists crazing, cracking, and chipping. Recirculated air diffuser materials shall be tested in accordance with UL Standard 94. Nonrigid diffuser materials shall conform to Class 94HBF; rigid diffuser materials shall conform to Class 94HB.

18 See Annex H for material selection guidance.

4.4 Other interior and exterior surfaces

Other interior and exterior surfaces shall be smooth and abrasion- and corrosion-resistant or shall be rendered corrosion-resistant with nontoxic materials that resist crazing, cracking, and chipping.

4.5 Materials and finishes

4.5.1 Windows

Windows shall be optically clear and not adversely affected by accepted cleaning methods and decontaminating agents. Glazing materials shall be laminated glass, tempered glass, safety plastic, or equivalent. Edges shall be ground or provided with protective stripping.

4.5.1.1 Flammability

Safety plastic view screens shall be tested in accordance with UL Standard 94 and conform to Class

94HB.

4.5.1.2 Abrasion resistance

Windows shall be abrasion-resistant and show no more than 5% change in haze when tested in accordance with 5.17, Test No. 17 of ANSI Standard 226.1.

4.5.2 Protective coatings

4.5.2.1 Chemical resistance

Protective coatings shall be resistant to prolonged contact to liquids, cleaning compounds, and procedures. Specifically, the protective coatings used shall be resistant to the following chemicals, when tested in accordance with annex D:

– 1N hydrochloric acid;

– 1N sodium hydroxide;

– 1% quaternary ammonium compound;

– 5% formaldehyde;

– 5000 ppm hypochlorite;

– 2% iodophor;

– 5% phenol; and

– 70% ethyl alcohol (ethanol).

When a coating is exposed to these chemicals following the test methods in annex D, there shall be no visible effect on the finish other than a slight change of gloss, discoloration, and/or temporary softening of the finish, with no loss of adhesion or film protection.

NOTE – When special chemical solutions are intended to be used, the resistance of the material thereto shall also be evaluated.

4.5.2.2 Abrasion resistance

Protective coatings for exposed interior, other interior, and exterior surfaces shall meet the following requirements when tested in accordance with annex D:

– maximum weight loss – 100 mg; and

– minimum wear value – 500 cycles.

4.5.3 Plastics

Plastics shall meet the applicable requirements of 4.1, 4.3, 4.4, and 4.5.1.

4.5.4 Welding

Welded seams and deposited weld material shall meet the applicable requirements of 4.1, 4.2, 4.3, and 4.4.

4.5.5 Gaskets and sealants

Gaskets and sealants shall be closed cell, durable, resistant to cleaning and disinfecting agents, and resistant to general use. They shall be made of materials that do not release halogens and are non-hardening, nontoxic, stable, odor free, not detrimentally absorbent, and unaffected by exposure to gases, liquids, cleaning compounds, and decontamination agents listed in 4.5.2.

Exposed surfaces of gaskets for all access panels, doors, structural seams, and windows shall be skinned and smooth. Gaskets supplied with HEPA/ULPA filters shall be exempt from this requirement.

4.5.6 Sound dampening

Sound-dampening materials shall conform to the requirements for the area in which they are used. They shall not be used in areas subject to contamination. Non-hardening and porous types shall not be accepted.

4.5.7 Hard solder

Hard (silver) solder shall be formulated to be corrosion-resistant.

5 Design and construction

5.1 General

Cabinets shall be designed and constructed to function properly and operate in a safe manner, minimize contamination, provide personnel and product protection, and be capable of being cleaned and decontaminated. Exposed burrs and sharp edges (including, but not limited to, sheet metal screws) shall be eliminated from surfaces of the cabinet that are subject to normal operation, field certification, and maintenance (including those maintained with simple tools).

5.2 Canopy Connect Exhaust

The external exhaust shall draw air sufficient to capture all exhaust from the BSC and to maintain a flow of air into the exhaust connection through the openings or gaps. The flow of air through the openings or gaps provides a buffer between the BSC exhaust and variation in the external exhaust system assuring consistent BSC performance and/or containment of volatile chemicals used in the BSC. Properly sized canopy openings or gaps also provide enough relief open area, so that if the cabinet exhaust system fails, the BSC will continue to function as if it was not connected to an exhaust system and continue to provide biological and particulate containment only. The canopy connection type of BSC exhaust connection is required for externally vented Class II, Type A1 or A2 BSCs.

5.3 Direct Connect Exhaust

The external exhaust shall draw air sufficient to capture all exhaust from the BSC and maintain a negative pressurization in the exhaust duct. The direct connection type of BSC exhaust connection is required for Class II, Type B1 or B2 BSCs.

5.2 Cleanability

Interior work, exposed interior, and the other interior surfaces subject to splash or spillage shall be readily accessible and easily cleanable as assembled or when removed. Interior work, exposed interior, and other interior surfaces, including plenums, shall be capable of being vapor or gas decontaminated.

5.3 Decontamination19

Cabinets shall be designed to be decontaminated with an inactivating agent (such as formaldehyde gas) without being moved. Closure to contain decontaminating agents should be limited to gas-tight sealing of air intake and exhaust openings with metal plates, or plastic film and tape, or equivalent.

Pressure tight valves, if provided, suitable for decontamination shall be located on the clean side of the HEPA/ULPA filter.

5.4 Duct and Plenum design

All biologically contaminated ducts and plenums in Types A1, A2, B1, and B2 cabinets shall be maintained under negative pressure or enclosed within a negative pressure zone.

5.5 Internal corners and angles

5.5.1 Interior work surfaces

5.5.1.1 Two-plane intersection

An internal angle of 2 rad (110°) or less formed by the intersection of two planes, which is subject to manual cleaning, shall have a minimum continuous and smooth radius of 0.13 in (3.2 mm) (see figure 2).

5.5.1.2 Three-plane intersection

An internal corner formed by the intersection of three planes at 2 rad (110°) or less, subject to manual cleaning, shall have a minimum continuous and smooth radius of 0.25 in (6.3 mm) for a vertical or horizontal intersection. The alternate intersections shall have a minimum continuous and smooth radius of

0.13 in (3.2 mm) (see figure 2).

5.5.1.3 Fillet material

Parent material or hard solder may be used as fillet material in structurally sound seams.

5.6 External corners and angles

All external corners and angles subject to splash or spillage or both…